NSW Liberals' campaign moving forward sans federal MPs

The sole Liberal leading a mainland state government won't rely on federal MPs as he campaigns to keep NSW moving forward beyond the March election.

NSW Premier Dominic Perrottet will head into Sydney's southwestern suburbs for the Liberal Party's official campaign launch on Sunday.

The area will be decisive in who wins the March 25 election, with the notionally Labor seat of Leppington and the Liberals' Holsworthy both on small margins.

The poll also provides voters an opportunity to send a message to local MPs and the government after suffering some of the harshest COVID-19 lockdown restrictions.

While key ministerial allies will help Mr Perrottet rally party faithful under the banner "Keep NSW moving forward", federal Opposition Leader Peter Dutton and other federal MPs will be notably absent from Sunday's event.

The premier has gambled his election chances on mega transport projects through the west, support for small businesses and energy bill relief to households.

He's increasingly leaned on the long-held Liberal Party messaging of being better economic managers as voters grapple with cost of living pressures and a rental crisis pushing some to the brink.

Recent political polls suggest a tight race, with a Labor minority government as the most likely result.

A decisive seat is Holsworthy, held by the Liberals on a six per cent margin, where the sitting MP Melanie Gibbons was dumped at preselection.

In her place sits Tina Ayyad, a former deputy mayor and the wife of Liverpool Mayor Ned Mannoun.

The Liberals would also need to retain East Hills (0.1 per cent margin) and regain the southern Sydney electorate of Heathcote (notionally Labor) to keep its grip on government.

The Liberals are the last of the lower house parties to launch their campaign.

The Greens on Saturday outlined their demands if Labor needed their support to form government.

Federal Greens leader Adam Bandt endorsed a pledge to scrap the proposed Narrabri Gas Project and related pipeline through the Hunter.

The project is on track to be completed in 2026 and is projected to eventually supply half of NSW's gas.

"We cannot afford new coal and gas. It's deadly, it's dangerous and it will cost us the earth," federal Greens leader Adam Bandt told the party faithful in Sydney.

Labor dismissed talk of minority government, focusing on winning the required 47 seats to rule in their own right.

"The only way to guarantee a change of government ... is to vote for a Labor candidate on the 25th of March," Labor leader Chris Minns said on Saturday.

With redistributions and resignations, the coalition has claims on 45 seats, Labor 38, the Greens three and independents seven in the 93-seat lower house.

Some 562 candidates are running in the lower house, with a candidate from Labor, the Greens and either the Nationals or the Liberals in every seat.

The Nationals and Liberals will face off in independent-held Wagga Wagga and Port Macquarie, held by National-turned-Liberal Leslie Williams.